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This Concept Map, created with IHMC CmapTools, has information related to: Answers_flagella, A motile response to an environmental stimulus. types of taxis thermotaxis: a motile response to temperature, A motile response to an environmental stimulus. types of taxis osmotaxis: a motile response to osmotic pressure, A basal body consisting of a rod and a series of rings that anchor the flagellum to the cell wall and the cytoplasmic membrane. function of basal body Acts as a rotary molecular motor, enabling the flagellum to rotate and propel the bacterium through the surrounding fluid; powered by proton motive force., flagella flagellar arrangements peritrichous: Flagella over the entire surface., A motile response to an environmental stimulus. polar flagella Some bacteria with polar flagella can only rotate their flagellum clockwise., A rigid, helical structure that extends from the bacterial surface and composed of the protein flagellin. role in body defense Bacterial flagellin functions as a pathogen-associated molecular pattern or PAMP that binds to pattern-recognition receptors or PRRs on a variety of defense cells of the body and triggers innate immune defenses., A motile response to an environmental stimulus. polar flagella Most bacteria with polar flagella can rotate their flagella both clockwise and counterclockwise., Organelles of locomotion for most bacteria capable of motility. benefits of motility Motility and chemotaxis probably help some intestinal pathogens to move through the mucous layer so they can attach to the epithelial cells of the mucous membranes. It also enable spirochetes to move through viscous environments and penetrate host cell membranes., Most bacteria with polar flagella can rotate their flagella both clockwise and counterclockwise. direction of rotation If the flagellum is rotating counterclockwise, it pushes the bacterium forward., Clockwise rotation results in a tumbling motion and changes the direction of bacterial movement. attractants and repellants When the bacterium is exposed to a chemical gradient of an attractant, it tumbles less frequently (has longer runs) as it moves up the gradient, but tumbles at the normal rate if it travels down the gradient. In this way, the net movement is towards a more optimum environment., Motility serves to keep bacteria in an optimum environment via taxis. taxis A motile response to an environmental stimulus., Bacteria with peritrichous flagella can rotate their flagella both clockwise and counterclockwise. swarming motility When bacteria with a peritrichous arrangement grow on a nutrient-rich solid surface, they can exhibit a swarming motility wherein the bacteria elongate, synthesize additional flagella, secrete wetting agents, and move across the surface in coordinated manner., flagella flagellar arrangements amphitrichous: A single flagellum at both ends of the organism., Clockwise rotation results in a tumbling motion and changes the direction of bacterial movement. attractants and repellants When the bacterium is exposed to a chemical gradient of a repellent, it tumbles less frequently (has longer runs) as it moves down the gradient, but tumbles at the normal rate if it travels up the gradient. In this way, the net movement is towards a more optimum environment., Bacteria with peritrichous flagella can rotate their flagella both clockwise and counterclockwise. direction of rotation Clockwise rotation results in a tumbling motion and changes the direction of bacterial movement., flagella flagellar arrangements monotrichous: A single flagellum, usually at one pole., Organelles of locomotion for most bacteria capable of motility. benefits of motility Motility serves to keep bacteria in an optimum environment via taxis., Some bacteria with polar flagella can only rotate their flagellum clockwise. direction of rotation Clockwise rotation pushes the bacterium forward. Everytime the bacterium stops, brownian motion and fluid currents cause the bacterium to reorient in a new direction., A motile response to an environmental stimulus. types of taxis aerotaxis: a motile response to oxygen, Bacteria with peritrichous flagella can rotate their flagella both clockwise and counterclockwise. direction of rotation Counterclockwise rotation leads to long, straight or curved runs without a change in direction.